Noometry

Model comparison

Claude Opus 5.5 vs Nemotron 3 Ultra

Claude Opus 5.5 is the stronger model overall, scoring 68.6 to 42.5 on the Noometry Index. Nemotron 3 Ultra costs 8.6× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.

Last verified . 26 shared benchmarks.

Claude Opus 5.5 Anthropic

68.6

Rank #3 Confirmed

Nemotron 3 Ultra NVIDIA

42.5

Rank #113 Confirmed

Summary

  • They share 26 benchmarks with published results for both. Claude Opus 5.5 scores higher in 9 categories and Nemotron 3 Ultra in 0 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in math, where Claude Opus 5.5 leads 91.8 to 35.3.
  • The biggest single-benchmark swing is ProofBench: 100% for Claude Opus 5.5 and 2% for Nemotron 3 Ultra.
  • Nemotron 3 Ultra is cheaper at $0.50 / $2.20 per million input/output tokens, against $4 / $20 for Claude Opus 5.5.
  • Claude Opus 5.5 accepts more context: 1M tokens versus 262K.
  • Nemotron 3 Ultra has downloadable open weights; the other is API-only.

Side by side

Claude Opus 5.5Nemotron 3 Ultra
ProviderAnthropicNVIDIA
Noometry Index68.642.5
Released2026-09-222026-06-04
WeightsProprietaryOpen
Context window1M262K
Max output128K128K
Input $ / M tokens$4$0.50
Output $ / M tokens$20$2.20
Results tracked4430

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Category by category

Coding Claude Opus 5.5 leads

Claude Opus 5.5: 71.9 (#3), Nemotron 3 Ultra: 38.1 (#182)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
FrontierCode54.6%13.6%
SciCode66.9%40.3%
LMArena Coding15471468
CursorBench57.8%—
LMArena WebDev1813—
FrontierSWE62.3%—
WeirdML—43.5%
MirrorCode77.4%—
ALE-Bench2,147—

Agentic & Tool Use Claude Opus 5.5 leads

Claude Opus 5.5: 45.3 (#15), Nemotron 3 Ultra: 23.4 (#126)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
APEX-Agents73.5%22.7%
GDP.pdf30.6%—
Vending-Bench 29,235—

Reasoning Claude Opus 5.5 leads

Claude Opus 5.5: 80.2 (#3), Nemotron 3 Ultra: 31.0 (#82)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
CritPt31.7%3.1%
LMArena Hard Prompts15351452
Mystery Game Puzzles71%20%
DTBench98.9%90.1%
LMCA68.2%36.9%
Epoch Capabilities Index167.33146.17
ARC-AGI-293.3%—
NYT Connections (extended)88.5%—
ARC-AGI-198.5%—
Chess Puzzles—12%
EBR-Bench71.4%—

Math Claude Opus 5.5 leads

Claude Opus 5.5: 91.8 (#3), Nemotron 3 Ultra: 35.3 (#187)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
OTIS Mock AIME 2024-2025100%86.7%
ProofBench100%2%
LMArena Math15061457
FrontierMath (Tiers 1-3)91.2%—
FrontierMath Tier 495%—
FrontierMath Erdős2.9%—

Knowledge Claude Opus 5.5 leads

Claude Opus 5.5: 66.4 (#10), Nemotron 3 Ultra: 52.5 (#61)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
GPQA Diamond90.6%85.4%
LMArena Expert15471472
SimpleQA Verified72.2%—

Multimodal Not comparable

Claude Opus 5.5: 57.8 (#1), Nemotron 3 Ultra: —

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
LMArena Vision1321—
Blueprint-Bench 251.2%—
Furniture Assembly83.3%—

Multilingual Claude Opus 5.5 leads

Claude Opus 5.5: 59.1 (#2), Nemotron 3 Ultra: 53.5 (#64)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
LMArena Non-English15071427
LMArena Chinese15881497
LMArena French15141472
LMArena Russian15201417
LMArena Spanish15071454
LMArena German—1471
LMArena Korean—1386

Instruction Following Claude Opus 5.5 leads

Claude Opus 5.5: 80.0 (#3), Nemotron 3 Ultra: 74.7 (#88)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
LMArena Instruction Following15371418

Long Context Claude Opus 5.5 leads

Claude Opus 5.5: 47.1 (#19), Nemotron 3 Ultra: 43.9 (#81)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
LMArena Longer Query15321437

Writing & Preference Claude Opus 5.5 leads

Claude Opus 5.5: 78.2 (#3), Nemotron 3 Ultra: 66.3 (#36)

BenchmarkClaude Opus 5.5Nemotron 3 Ultra
LMArena Text15151445
LMArena Creative Writing15331398
EQ-Bench Creative Writing20501692
LMArena Multi-Turn14991411

Frequently asked questions

Is Claude Opus 5.5 better than Nemotron 3 Ultra?

Claude Opus 5.5 is the stronger model overall, scoring 68.6 to 42.5 on the Noometry Index. Nemotron 3 Ultra costs 8.6× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.

Which is cheaper, Claude Opus 5.5 or Nemotron 3 Ultra?

Nemotron 3 Ultra is cheaper. It lists at $0.50 per million input tokens and $2.20 per million output tokens; Claude Opus 5.5 lists at $4 and $20.

Is Claude Opus 5.5 or Nemotron 3 Ultra better for coding?

Claude Opus 5.5 scores higher on coding benchmarks: 71.9 versus 38.1 in the Noometry coding category.

Which has the bigger context window?

Claude Opus 5.5 does, with 1M tokens against 262K.

How many benchmarks do Claude Opus 5.5 and Nemotron 3 Ultra share?

26 benchmarks have published results for both models. Claude Opus 5.5 has 44 scored results on Noometry and Nemotron 3 Ultra has 30.

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